Use of maraviroc in patients with undetectable viral load: efficacy, tolerance and predictors of viral response in MARAVIROC-cohort study

INTRODUCTION No controlled clinical trials had studied the role of maraviroc (MRV) in fully suppressed patients (1). MATERIALS AND METHODS MRV-cohort is an observational, retrospective, multicentric (27 sites) large cohort study of patients starting MRV in clinical practice under different circumstances, with at least 48 weeks of follow-up. For the present analysis we selected all those patients starting with an HIV-RNA<50 copies/mL. Demographics, baseline CD4 cell count, past history of antiretroviral treatment (ART), tropism, reasons for MRV use, MRV based therapy and change/end of MRV use were assessed. Paired analysis of lipid, hepatic and kidney profile changes and univariate and multivariate analyses of HIV-RNA<50 copies/mL at 48 weeks were explored. RESULTS We included 247 out of 667 subjects from the entire cohort. At study entry, their median age was 47 years, 23% were women, 31% MSM, 49% had CDC category C, median CD4+ counts were 468 cells/mm(3), 46% were HCV+ and 4.5% AgHBs+. Tropism information was available in 197 (94% R5). Median length of prior ARTV was 10.7 years, with exposure to a median of three drug families. Main reasons for prescribing MRV were: toxicity 38%, inmunodiscordance 23%, simplification 19% and admission in a clinical trial 10.4%. MRV based therapies used were MRV+2NRTIs 9%, MRV+PI 46%, MRV+PI+other 40% and MRV+other 5%. At 48 weeks, 23% of patients had changed or finished MRV therapy due to toxicity 2.4%, virological failure 2%, immunological failure 1.2%, simplification 3,2%, trial requirement 9.7%, medical decision 2.8%, treatment suspension 1.2% and unknown 0.4%. At 48 weeks, no significant changes were observed in lipid, hepatic or kidney profiles, and 85% of patients remained with HIV-RNA<50 copies/mL. Focusing on viral response univariate and multivariate models did not show any significant baseline variable explaining viral failure. CONCLUSIONS In clinical practice MRV was used, mostly in R5 positive patients, with adequate efficacy and tolerance, but important number of patients changed due to non-clinical reasons. In this scenario neither reason for use of MRV nor MRV-based therapy explained viral failure.